Protein Core (William Marzluff., Faculty Director) Nucleic acid technology has evolved at an extraordinary rate and will, for all intents and purposes, complete sequencing of the human genome within the next CCSG five-year cycle. Other efforts will create substantial sequence databases from the mouse, and complete sequences are extant, or soon will be, for most lower organisms. The next era of discovery will rely much less on the sequencing of unknown nucleic acid clones, and much more on detecting and identifying proteins purified by virtue of their function or interaction with other proteins. Thus, a forward-looking core facility to identify proteins and study multiple facets of protein interactions will be of increasing importance to the UNC Lineberger. Although the CCSG has not previously funded a protein core, several components are functioning at UNC. The current proposal takes those operationalized components and combines them under one administrative structure, directed by William Marzluff, Ph.D., Cancer Center Associate Director for Core Facilities and Director for the Program of Molecular Biology and Biotechnology (PMBB). The Protein Core will include: (1) a multifaceted facility for studying biochemistry and the chemistry of protein-protein interactions; (2) a peptide synthesis facility to provide peptides for study of interactions in pure systems, as reagents to disturb cellular interactions in cell culture, and for use as antigens to raise antibodies.; (3) protein purification and peptide isolation; and (4) high sensitivity peptide sequencing, involving either Edman degradation, or, increasingly mass spectroscopy analysis of peptides.